Governor cable take-up



Jan. 3, 1939.

T. c. HARPER GOVERNOR CABLE TAKE-U1" Filed May 3, 1957 I INVENTOR.

7/20/7745 Qfla/per ATTORNEYS Patented Jan. 3, 1939 UNITED STATES PATENTOFFICE GOVERNOR CABLE TAKE-UP Ill.

Application May 3, 1937, Serial No. 140,468

1 Claim.

This invention relates to elevators and particularly that type employinga cable suspended cab or cage that is raised and lowered in an elevatorshaft and which has as a part of its operating equipment a governorcable which is suspended in looped fashion so that the bight is at thebottom or in the conventional pit of the elevator shaft.

The primary object of this invention is the pro- '10'vision of anautomatic takeup structure for the governor cable of elevators whichstructure embodies uniquely arranged elements whereby the governor cableis engaged at the bight thereof and yieldably held in a taut position.

Another important aim of the instant invention is to provide governorcable takeup structure which has means for engaging the bight of agovernor cable and for yieldably holding the bight in one of a number ofpositions all in accordance with the amount of stretch imparted to thegovernor cable during work.

A large number of elevator governor cable takeup mechanisms have beenemployed commercially in an effort to overcome the well knownobjectionable slap that occurs in the elevator cable after the same hasbeen once installed and after continued use has established a largeamount of play that is not compensated for by the conventional elevatormechanism. Ordinary Weights which have been hung at the bight ofelevator governor cables have been used for a long time past but suchweights do not overcome the wear on the governor cables which isoccasioned by the presence of an excessive amount of play in 5 the cablewhich invariably develops after strain has been imparted thereto throughthe ordinary operating routine.

This invention, therefore, contemplates the employment of novel meansfor yieldably main- 4() taining a pulley wheel in engagement with thebight of a governor cableso that as the cable lengthens due to work, thesame amount of yieldable pressure will always be imparted regardless ofthe degree or speed of stretch and without 5 attention of a maintenanceman.

Minor objects of the invention which will include specific embodimentsof one form of the invention willappear during the course of thefollowing specification, referring to the accompany- 50 ing drawingwherein;

Figure 1 is a side elevation of an elevator governor cable takeupstructure made to embody the present invention.

Fig. 2 is a vertical sectional view through the 55 structure taken online II-II of Fig. 1.

Fig. 3 is a top plan view of the structure shown in Fig. 1, and,

Fig. 4 is an enlarged, fragmentary, detailed sectional view through aportion of the takeup structure taken on line IVIV of Fig. 2. 5

The governor cable 6 which forms a part of the elevator mechanism islooped at the bottom of the elevator shaft to present a bight whereinrides the conventional pulley wheel 8. There is always a certain amountof variation in the pre- 10 cise position of the bight and accordinglypulley wheel 8 must give and take as required. It is always customary tohave pulley 8 removably mounted so that vertical travel may be had tocompensate for the conditions just mentioned 5 and which are well known.In the instance shown pulley wheel 8 is rotatably mounted in theweighted wheel frame I!) through the medium of transverse pintle I2 thatis carried by opposed members I4 of said frame ll]. 20

The structure provided to present tracks l6 along which frame It] mayride is in the nature of an open frame work including an upper and alower support arm l8 and 20 which may be mounted upon a part of theelevator track 22 or 25 anchored to any other relatively stationary andsolid member in the bottom of the elevator shaft. The weighted wheelframe I0 is confined between tracks 56 and may move verticallythere-between as the tracks preclude lateral displacement. 30

A ratchet bar 24 extends vertically beside frame In and isprovided witha plurality of teeth 26. The lower end of bar 24 has a foot 28 turnedtherefrom to overlie bottom support arm 20 and to rest thereon therebyto preclude any downward movement of bar 24 when foot 28 is in theposition illustrated in Fig. 2. A bolt 30 extends through an openingformed in foot 28 and through a hole 32 provided in arm 20. The lengthof this bolt 30 may vary in accordance with conditions met and a spring34 of suitable strength is coiled about bolt 30 so that one end bearsagainst arm 20 while the other end engages washer 36 held in place bynut 38. Thus it is apparent that upward vertical movement by bar 24 mayoccur so long as the upward force imparted thereto is sufficient toovercome the strength of spring 34.

Wheel frame ID has a bracket 40 secured thereto as clarified in Fig. 4.This bracket 40 has opposed outstanding ears between which is mounted adog 42 that is specially formed to engage teeth 26 of bar 24. This dogis bifurcated at its free end as at 44 so that there is presented aprojecting portion that is disposed on each side of bar 24. The otherend of dog 42 is curled to present a bearing as shown in Fig. 4 whichbearing has a bolt 46 extended therethrough so that free rotary motionmight occur. This movement however, is limited by a stop 48 so that thedog will always remain in such a position as to require the action ofgravity to move it against teeth 26 of bar 24. Teeth 26 are so formed asto permit dog 42 to ride'thereover when the pulley wheel and frame 8 andI0 respectively are traveling downwardly but when an upward movementoccurs dog 42 tightly engages one of the teeth 26 so that any suchupward movement is manifestly opposed by the tension of spring 34. Thusit will be clear to one skilled in the art that as governor cable 6lengthens to permit its bight to gradually lower, the dog 42 which iscarried by frame 10 will move down along bar 24 to progressively engagethe teeth 26 formed therein. After the frame has been lowered to a pointfor example as shown in the drawing, any upward movement on the part ofthe bight of cable 6 would be opposed by spring 34 because of therelation between the elements. 7

Wearing of cable 6 because of an excessive amount of slack due to playtherein will be overcome and it has been found through actual use ofthis structure that the cable life is prolonged, the strands thereof arenot broken as a result of inner engagement with each other due to thelooping of the cable and that a smooth action is always insured when theelevator cab is stopped.

It is conceivable that governing structure for elevator takeup cableswhich embody this invention might be made to present a physicalappearance much difierent from that illustrated and it is desired to belimited only by the spirit of the invention and scope of the appendedclaim.

I claim:

In an elevator governor-cable assembly having a pulley wheel in thebight of the cable, a vertically movable frame rotatably supporting thepulley wheel to move therewith as the bight of the cable raises andlowers, and a stationary guide with spaced apart guide tracks for theframe, a vertical bar provided with ratchet teeth, carried by the guidesubstantially midway between said tracks and disposed beside a portionof the frame; a spring having connection with the guide and with saidbar to yieldably hold the bar in a normal position for longitudinalmovement upward; ly from the normal position; and a dog mounted on theframe in engagement with the ratchet teeth of the bar, said teeth anddog being formed and disposed respectively so as to cause the frame, dogand bar to move upwardly together when the spring yields under theaction of the governorcable and to cause the dog and frame to movedownwardly independently of the bar when the same is in the normalposition.

THOMAS C. HARPER.

